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Crew, L.

Publications and source records attributed to Crew, L..

2 recordsLinked to original sources

The Impact of Formic Acid Treatment on Brain Tissues for Prion Inactivation

There are significant risks in clinical, diagnostic, and research settings to those who investigate prion diseases, due to the difficult nature of inactivating prion proteins with standard decontamination methods. Formic acid treatment has been shown to be effective for decontaminating infectious prions and commonly used in biosafety practice to prevent occupational exposure. However, the impact of formic acid protocols on the morphology of tissue samples has not been adequately documented. The goal of this study is to examine morphologic effects of formic acid treatment on central nervous system tissue, using mouse model brain hemisphere tissues that exhibit varying degrees of neurodegeneration as a model. This study included normal, non-diseased wild-type tissues and a 5xFAD model, which recapitulates aspects of Alzheimers Disease (AD). A model exhibiting Chronic Wasting Disease (CWD), a prion disease of deer and elk, was also used to analyze the effects of formic acid on tissues with spongiform changes. Tissues from both formic acid and untreated control treatment groups were embedded in paraffin, sectioned, stained, and imaged microscopically. Anatomical regions were analyzed and evaluated quantitatively to determine the width, area, and structural integrity of the tissue between treatment groups. Our findings demonstrated that while formic acid has been previously reported to effectively inactivate prions, it compromised the morphology of mouse brain tissues. Furthermore, the effects of formic acid were not distributed equally between regions of the brain. Age did not play a role in the morphologic changes seen in the formic acid treatment group. Interestingly, the presence of neurodegeneration in the tissues did not appear to exacerbate the effects of morphological changes post-formic acid treatment. These results emphasize the need to explore alternative prion inactivation methods that ensure the safety and reliability of handling prion-infected tissues without compromising the integrity of tissues.

pathology↗

Neurological Tissue Dissection Techniques in Mouse Models for Reproducible Scientific Results: Brain, Spinal Cord, CSF, and Sciatic Nerve

Biomedical research studies, specifically regarding human neurodegenerative diseases, are bound by ethical challenges, and have limited diagnostic and treatment options. Transgenic mouse models offer an incredible research advantage to conduct feasible and practical research with the ability to precisely define the progression of neurodegenerative disease over a wellcontrolled dosage and timeline. The use of transgenic mouse models has been extensive and is critical to advancing research in many ways, including understanding brain morphology and general tissue changes caused by neurological diseases. Often, these studies require specific brain regions or other neurological tissues which may be difficult to obtain. Unfortunately, specific extraction and dissection protocols are few and far between, leading to inconsistent results and a lack of reproducibility. A well-defined protocol, such as this, is instrumental in overcoming these obstacles and acquiring better experimental results. Five mouse-specific protocols are described: brain extraction, brain microdissection, spinal cord extrusion, cerebral spinal fluid (CSF) collection, and sciatic nerve dissection. Each protocol was completed under biosafety level 2 (BSL-2) guidelines, similar to the sterility precautions required in human surgery. Each protocol also includes a collective materials list that defines proper instruments and usage. The protocol was refined based on feedback from numerous research studies in transcriptomics and pharmaceutical development. These applications require minimizing tissue damage, dissection accuracy, and the ability to reproduce the results--skills that are also directly transferable to clinical settings. The proper implementation of these protocols will allow for more accurate and precise results with reduced variability. This study provides well-defined, succinct, accessible protocols that are more ethical and improve the overall quality of the conducted research. By addressing this need, it supports greater advancements in many cross disciplinary areas.

neuroscience↗